Overview
The TMP04FS, produced by Analog Devices Inc., is a monolithic temperature detector that generates a modulated serial digital output. This output varies in direct proportion to the temperature of the device. The sensor uses an onboard temperature sensor to generate a voltage that is precisely proportional to absolute temperature, which is then compared to an internal voltage reference and input to a precision digital modulator. This ratiometric encoding format ensures that the output is independent of clock drift errors common in other serial modulation techniques.
Key Specifications
| Parameter | Symbol | Conditions | Min | Typ | Max | Units |
|---|---|---|---|---|---|---|
| Temperature Error | - | TA = 25°C | 1.0 | 3.0 | - | °C |
| Temperature Error | - | -25°C < TA < +100°C | 1.5 | 4.0 | - | °C |
| Temperature Error | - | -40°C < TA < -25°C | 2.0 | 5.0 | - | °C |
| Temperature Linearity | - | - | - | 0.5 | - | °C |
| Long-Term Stability | - | 1000 Hours at 125°C | - | 0.5 | - | °C |
| Nominal Mark-Space Ratio T1/T2 | - | TA = 0°C | - | 58.8% | - | % |
| Nominal T1 Pulse Width | T1 | - | - | 10 ms | - | ms |
| Power Supply Rejection Ratio (PSRR) | - | Over Rated Supply | 0.7 | 1.2 | - | °C/V |
| Output High Voltage (VOH) | - | IOH = 800 µA | - | V+ – 0.4 V | - | V |
| Output Low Voltage (VOL) | - | IOL = 800 µA | - | 0.4 V | - | V |
| Digital Output Capacitance (COUT) | - | - | - | 15 pF | - | pF |
| Fall Time (tHL) | - | See Test Load | - | 200 ns | - | ns |
| Rise Time (tLH) | - | See Test Load | - | 160 ns | - | ns |
| Supply Voltage Range | V+ | - | 4.5 V | - | 7 V | V |
| Operating Temperature Range | - | - | -40°C | - | 100°C | °C |
Key Features
- High Accuracy: The TMP04FS offers high accuracy with a temperature error of ±1.5°C (typical) from –25°C to +100°C and ±2.0°C (typical) from –40°C to –25°C.
- Ratiometric Encoding: The output is encoded in a ratiometric format, making it independent of clock drift errors, which is beneficial for precise temperature measurement.
- CMOS/TTL Compatibility: The digital output of the TMP04FS is CMOS/TTL compatible, making it easily interfaced with most microprocessors.
- Low Power Consumption: Operating from +5 V, the supply current (unloaded) is less than 1.3 mA.
- Compact Packaging: Available in TO-92, SO-8, and TSSOP-8 surface mount packages, making it suitable for various applications.
- PWM Output: The output is a square wave with a nominal frequency of 35 Hz (±20%) at +25°C, which can be easily decoded by the user.
Applications
- Industrial Automation: Suitable for temperature monitoring in industrial automation systems where high accuracy and reliability are crucial.
- Medical Devices: Can be used in medical devices that require precise temperature measurement and control.
- Aerospace and Defense: Applicable in aerospace and defense systems where temperature monitoring is critical for system reliability and performance.
- Consumer Electronics: Used in various consumer electronics for temperature sensing and control, such as in HVAC systems and smart home devices.
- Automotive Systems: Suitable for temperature monitoring in automotive systems, including engine management and climate control systems.
Q & A
- What is the temperature range of the TMP04FS?
The TMP04FS operates over a temperature range of –40°C to +100°C, with extended operation up to +150°C with reduced accuracy.
- What is the typical accuracy of the TMP04FS?
The typical accuracy is ±1.5°C from –25°C to +100°C and ±2.0°C from –40°C to –25°C.
- What is the output format of the TMP04FS?
The output is a modulated serial digital output in a ratiometric format, which is independent of clock drift errors.
- Is the TMP04FS compatible with CMOS/TTL systems?
Yes, the digital output of the TMP04FS is CMOS/TTL compatible.
- What is the supply voltage range for the TMP04FS?
The supply voltage range is from 4.5 V to 7 V.
- How much current does the TMP04FS consume?
Operating from +5 V, the supply current (unloaded) is less than 1.3 mA.
- What are the available package types for the TMP04FS?
The TMP04FS is available in TO-92, SO-8, and TSSOP-8 surface mount packages.
- How is the temperature calculated from the output of the TMP04FS?
The temperature is calculated by measuring the T1 and T2 periods of the output signal and using the provided equation to determine the temperature.
- Is the TMP04FS suitable for isolated circuits?
Yes, the TMP03 (a variant of the TMP04) is best suited for systems requiring isolated circuits utilizing optocouplers or isolation transformers.
- What is the nominal frequency of the output signal at +25°C?
The nominal frequency of the output signal at +25°C is 35 Hz (±20%).
